On 17/11/2023 16:20, Théo Lebrun wrote: > Hi Roger, > > On Fri Nov 17, 2023 at 12:51 PM CET, Roger Quadros wrote: >> On 17/11/2023 12:17, Théo Lebrun wrote: >>> On Thu Nov 16, 2023 at 10:44 PM CET, Roger Quadros wrote: >>>> On 16/11/2023 20:56, Théo Lebrun wrote: >>>>> On Thu Nov 16, 2023 at 1:40 PM CET, Roger Quadros wrote: >>>>>> On 15/11/2023 17:02, Théo Lebrun wrote: >>>>>>> On Wed Nov 15, 2023 at 12:37 PM CET, Roger Quadros wrote: >>>>>>>> You might want to check suspend/resume ops in cdns3-plat and >>>>>>>> do something similar here. >>>>>>> >>>>>>> I'm unsure what you are referring to specifically in cdns3-plat? >>>>>> >>>>>> What I meant is, calling pm_runtime_get/put() from system suspend/resume >>>>>> hooks doesn't seem right. >>>>>> >>>>>> How about using something like pm_runtime_forbid(dev) on devices which >>>>>> loose USB context on runtime suspend e.g. J7200. >>>>>> So at probe we can get rid of the pm_runtime_get_sync() call. >>>>> >>>>> What is the goal of enabling PM runtime to then block (ie forbid) it in >>>>> its enabled state until system suspend? >>>> >>>> If USB controller retains context on runtime_suspend on some platforms >>>> then we don't want to forbid PM runtime. >>> >>> What's the point of runtime PM if nothing is done based on it? This is >>> the current behavior of the driver. >> >> Even if driver doesn't have runtime_suspend/resume hooks, wouldn't >> the USB Power domain turn off if we enable runtime PM and allow runtime >> autosuspend and all children have runtime suspended? > > That cannot be the currently desired behavior as it would require a > runtime_resume implementation that restores this wrapper to its desired > state. > > It could however be something that could be implemented. It would be a > matter of enabling PM runtime and that is it in the probe. No need to > even init the hardware in the probe. Then the runtime_resume > implementation would call the new cdns_ti_init_hw. > > This is what the cdns3-imx wrapper is doing in a way, though what they > need is clocks rather than some registers to be written. > > That all feels like outside the scope of the current patch series > though. > > My suggestion for V2 would still therefore be to remove all PM runtime > as it has no impact. It could be added later down the road if cutting > the power-domain is a goal of yours. OK let's do this. -- cheers, -roger
